Field
The disclosed concept relates generally to acoustic event detection such as gunshot detection, and, more particularly, to speaker systems with acoustic event detection capability. The disclosed concept also relates to modification kits for speaker systems and methods of modifying speaker systems.
Background Information
Gunshot detection systems typically include a number of sound sensors, such as microphones, to detect the sound of a gunshot. The systems process the sounds received by the sound sensors to distinguish a gunshot from other sounds. Such systems may also determine the location of the gunshot. Example gunshot detection systems are disclosed in U.S. Pat. Nos. 7,961,550, 7,710,278, 7,719,428 and 7,688,679.
Gunshot detection systems can be employed in a variety of places such as buildings, urban areas, college or university campuses, etc. However, the cost of the gunshot detection system can be prohibitive. Among other costly factors is the requirement for known systems is installing and wiring geographically spaced sound sensors.
Many areas have speaker systems, such as alarm systems (e.g., without limitation, fire alarm systems) or mass notification systems, already installed and wired. FIG. 1 is a schematic diagram of a speaker system 1. The speaker system 1 of FIG. 1 includes a head unit 2 and a number of speakers 4 electrically connected in parallel to the head unit 2. An end-of-line resistor 6 is also electrically connected in parallel with the speakers 4.
The head unit 2 includes an alarm output circuit 7 and a supervision circuit 8. The output circuit 7 is structured to selectively output an alternating current signal such as an alarm signal which causes the speakers 4 to audibly output an alarm. Otherwise, when the output circuit 7 is not outputting the output signal, the speakers 4 remain silent. The supervision circuit 8 outputs a supervision signal that verifies that the end-of-line resistor 6 is in place and verifies the integrity of the wiring of the speakers 4. The supervision circuit 8 may output a direct current signal or an alternating current signal to verify the integrity of the wiring.
Speaker systems have not traditionally been used for purposes other than sounding alarm signals.
It would be beneficial to reduce the cost of a gunshot detection system.